Sidecar pattern in Microservices - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a sidecar container that runs alongside the main application container.

Microservices

containers:
  - name: main-app
    image: myapp:latest
  - name: sidecar
    image: [1]

Drag options to blanks, or click blank then click option'

Asidecar-proxy:latest

Bmain-app:latest

Cdatabase:latest

Dcache:latest

Attempts:

3 left

💡 Hint

Common Mistakes

Using the main application image for the sidecar container.

Using unrelated service images like database or cache.

The sidecar container typically runs a proxy or helper service, so the image should be a sidecar proxy image.

2fill in blank

medium

Complete the code to show how the sidecar pattern helps with logging in microservices.

Microservices

main_service_logs -> [1] -> centralized_logging_system

Drag options to blanks, or click blank then click option'

Aload_balancer

Bdatabase

Csidecar_container

Dcache

Attempts:

3 left

💡 Hint

Common Mistakes

Using database or cache which are unrelated to log forwarding.

Confusing load balancer with sidecar functionality.

The sidecar container collects logs from the main service and forwards them to a centralized logging system.

3fill in blank

hard

Fix the error in the description of the sidecar pattern usage.

Microservices

The sidecar pattern runs the helper service in a separate [1] from the main application.

Drag options to blanks, or click blank then click option'

Aprocess

Bcontainer

Cserver

Ddatabase

Attempts:

3 left

💡 Hint

Common Mistakes

Saying it runs as a separate process instead of container.

Confusing it with running on a separate server.

The sidecar pattern runs the helper service in a separate container, not just a process or server.

4fill in blank

hard

Fill both blanks to complete the sidecar pattern benefits.

Microservices

The sidecar pattern helps with [1] and [2] without changing the main application code.

Drag options to blanks, or click blank then click option'

Alogging

Bdatabase

Cmonitoring

Dcaching

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing database or caching which are not typical sidecar responsibilities.

Sidecar pattern is commonly used for logging and monitoring as helper services.

5fill in blank

hard

Fill all three blanks to complete the sidecar pattern example in Kubernetes YAML.

Microservices

containers:
  - name: app
    image: myapp:latest
  - name: [1]
    image: [2]
    ports:
      - containerPort: [3]

Drag options to blanks, or click blank then click option'

Asidecar-proxy

Bsidecar-logger

C15000

Dsidecar-proxy:latest

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong container names or images.

Incorrect port numbers.

The sidecar container is named 'sidecar-proxy', uses the 'sidecar-proxy:latest' image, and exposes port 15000.

Practice

1. What is the main purpose of the Sidecar pattern in microservices architecture?

easy

A. To split a service into multiple smaller services

B. To replace the main service with a new version

C. To store data separately from the service

D. To add extra features to a service without modifying its code

Solution

1. Step 1: Understand the Sidecar pattern role

   The Sidecar pattern runs alongside the main service to add capabilities without changing the service itself.

2. Step 2: Compare options with the pattern definition

   Replacing, splitting, or storing data separately are not the main goals of the Sidecar pattern.

3. Final Answer:

   To add extra features to a service without modifying its code -> Option D

4. Quick Check:

   Sidecar adds features without code change = C [OK]

Hint: Sidecar adds features beside service, no code change needed [OK]

Common Mistakes:

• Thinking Sidecar replaces the main service
• Confusing Sidecar with service splitting
• Assuming Sidecar stores data separately

2. Which of the following is the correct way to describe the deployment of a Sidecar in a microservices environment?

easy

A. It runs alongside the main service in the same environment

B. It runs as a separate service on a different server

C. It replaces the main service container

D. It runs only during service startup

Solution

1. Step 1: Recall Sidecar deployment setup

   The Sidecar runs alongside the main service, sharing the same environment like a container or pod.

2. Step 2: Eliminate incorrect deployment options

   Running separately, replacing the service, or running only at startup do not match the Sidecar pattern.

3. Final Answer:

   It runs alongside the main service in the same environment -> Option A

4. Quick Check:

   Sidecar runs beside service in same environment = A [OK]

Hint: Sidecar always runs beside main service, not separately [OK]

Common Mistakes:

• Assuming Sidecar runs on a different server
• Thinking Sidecar replaces the main service
• Believing Sidecar runs only once at startup

3. Consider a microservice with a Sidecar that handles logging. If the main service crashes, what happens to the Sidecar?

medium

A. The Sidecar also stops because it shares the same lifecycle

B. The Sidecar continues running independently

C. The Sidecar restarts the main service automatically

D. The Sidecar switches to a backup service

Solution

1. Step 1: Understand Sidecar lifecycle dependency

   The Sidecar runs in the same environment and shares lifecycle with the main service, so if the main service stops, the Sidecar usually stops too.

2. Step 2: Evaluate other options

   Sidecar does not run independently, restart the main service, or switch to backup automatically.

3. Final Answer:

   The Sidecar also stops because it shares the same lifecycle -> Option A

4. Quick Check:

   Sidecar lifecycle tied to main service = D [OK]

Hint: Sidecar shares lifecycle with main service, stops if service crashes [OK]

Common Mistakes:

• Thinking Sidecar runs independently after crash
• Assuming Sidecar restarts main service
• Believing Sidecar switches to backup automatically

4. A developer tries to implement a Sidecar for monitoring but deploys it on a separate server. What is the main issue with this approach?

medium

A. The Sidecar will automatically replace the main service

B. The Sidecar will consume too much CPU on the main server

C. The Sidecar cannot share the same environment and lifecycle with the main service

D. The Sidecar will cause the main service to crash

Solution

1. Step 1: Identify Sidecar deployment requirements

   Sidecar must run alongside the main service in the same environment to share lifecycle and resources.

2. Step 2: Analyze the problem of separate server deployment

   Deploying on a separate server breaks the Sidecar pattern because it loses environment and lifecycle sharing.

3. Final Answer:

   The Sidecar cannot share the same environment and lifecycle with the main service -> Option C

4. Quick Check:

   Sidecar must share environment; separate server breaks this = A [OK]

Hint: Sidecar must share environment; separate server breaks pattern [OK]

Common Mistakes:

• Thinking Sidecar causes CPU overload on main server
• Assuming Sidecar replaces main service automatically
• Believing Sidecar causes main service crash

5. You want to add secure communication (TLS encryption) to an existing microservice without changing its code. How does the Sidecar pattern help achieve this?

hard

A. By rewriting the service code to include TLS libraries

B. By deploying a Sidecar proxy that handles TLS encryption and decryption alongside the service

C. By moving the service to a secure server only

D. By disabling all external communication to the service

Solution

1. Step 1: Understand Sidecar role in adding features

   The Sidecar can run a proxy that manages TLS encryption without changing the main service code.

2. Step 2: Compare other options with Sidecar benefits

   Rewriting code, moving servers, or disabling communication do not use Sidecar advantages.

3. Final Answer:

   By deploying a Sidecar proxy that handles TLS encryption and decryption alongside the service -> Option B

4. Quick Check:

   Sidecar proxy adds TLS without code change = B [OK]

Hint: Sidecar proxy adds TLS, no code rewrite needed [OK]

Common Mistakes:

• Thinking code rewrite is needed for TLS
• Assuming moving servers secures communication alone
• Believing disabling communication is a solution